Principles of Evolution

March 4th, 2018 by Christine Chadwick

In science classes at most educational levels, it's difficult to avoid the theory of evolution formulated by Charles Darwin. In his famous book, On the Origin of Species, Darwin outlines his theory of evolution based upon the singular idea of natural selection. Natural selection suggests that the strongest traits, whether physical or psychological, will be passed down from generation to generation. Evolution occurs as a result of natural selection, which can also be described as a gradual loss of weaker traits.

In a nutshell, Darwin's theory of evolution involves three key principles: variability, differential fitness, and heritability.

1. Variability

This principle involves differences in genetic makeup among communities. Darwin noted unique physical and behavioural qualities among human groups that resulted out of pure chance. Alterations in genetics occur over time, as the traits that encourage survival are passed on to subsequent generations. These changes happen naturally, as new combinations of genes are created with each new generation. Reproduction causes genetic components from both parties to create an entirely new makeup of DNA in the offspring. As Darwin noted in the 19th century, variety in the DNA of people will always exist.

2. Differential Fitness

This principle involves the differentiation that will naturally occur within the makeup of one species to the next. Several unique factors affect the genetic composition of a society over time. For example, the environment in which a people finds itself living results in various traits being passed on or withheld from the next generation. Adaptation occurs as a direct result of where people and animals live. Traits that spur survival and thriving in a given society and environment will carry on, allowing for differential fitness in future generations.

3. Heritability

This third and final principle of evolution highlights the need for variation in societies in order for them to successfully proliferate themselves. Even early scientists theorising evolution noticed that a variety of genetic traits coming together produce a more dynamic, survivable creature. This is the reason why humans that share DNA should not procreate, as their offspring might be plagued by physical and mental mutations. Survival of the fittest is one of the key theories of Darwinian evolution and natural selection. It involves the strongest heritable traits being passed down from generation to generation.

Though evolution is a hotly debated topic in many circles, there is much scientific evidence that makes a case for its existence. Every species physically adapts and changes over time; this is an observable truth. Just how and why these adaptations occur is where the mystery sometimes lies. If you're interested in learning more about the theory of evolution, check out Darwin's On the Origin of Species.